Novel red-emitting phosphor Na3LaW3O12: Sm3+, Eu3+: synthesis, luminescent properties, anti-thermal quenching and LED packaging

A series of novel red-emitting Na₃LaW₃O₁₂: xSm³⁺ (x = 0–0.1) and Na₃LaW₃O₁₂: 0.06Sm³⁺, yEu³⁺ (y = 0.09–0.27) phosphors have been synthesized through a high-temperature solid-state method. The phase structure, luminescent properties, and thermal stability of these materials were analyzed by the X-ray diffraction, scanning electron microcopy, luminescence spectra, luminescence decay curves, and temperature-dependent spectra. The Na₃LaW₃O₁₂: Sm³⁺, Eu³⁺ phosphor show an abnormal thermal stability property, and the luminescence intensity of Na₃LaW₃O₁₂: 0.06Sm³⁺, 0.21Eu³⁺ at 453 K remains about 97% of the original value at room temperature. Based on the as-synthesized Na₃LaW₃O₁₂: 0.06Sm³⁺, 0.21Eu³⁺ phosphors as red component, a white LED with 2653 K correlated color temperature and R_a = 85.0 color rendering index has been fabricated using a 465 nm blue chip, and LuAG: Ce³⁺ yellowish-green phosphor. The results indicated that the as-synthesized Na₃LaW₃O₁₂: Sm³⁺, Eu³⁺ phosphor may be applied in white LEDs as potential abnormal thermal quenching red-emitting material.